# coding=utf-8
from __future__ import with_statement

# hack to import the proper path for having a working 'models.py'
import sys
from os.path import abspath, dirname

from alembic import context
from sqlalchemy import engine_from_config, pool

sys.path.insert(0, dirname(abspath(__file__)))
import models

# this is the Alembic Config object, which provides
# access to the values within the .ini file in use.
config = context.config

# Interpret the config file for Python logging.
# This line sets up loggers basically.
# fileConfig(config.config_file_name)

# add your model's MetaData object here
# for 'autogenerate' support
# from myapp import mymodel
# target_metadata = mymodel.Base.metadata

target_metadata = models.Base.metadata


# other values from the config, defined by the needs of env.py,
# can be acquired:
# my_important_option = config.get_main_option("my_important_option")
# ... etc.


def run_migrations_offline():
    """Run migrations in 'offline' mode.

    This configures the context with just a URL
    and not an Engine, though an Engine is acceptable
    here as well.  By skipping the Engine creation
    we don't even need a DBAPI to be available.

    Calls to context.execute() here emit the given string to the
    script output.

    """

    # if a database path was provided, override the one in alembic.ini
    database = context.get_x_argument(as_dictionary=True).get('database')
    if database:
        url = "sqlite:///%s" % database
    else:
        url = config.get_main_option("sqlalchemy.url")

    context.configure(
        url=url, target_metadata=target_metadata, literal_binds=True)

    with context.begin_transaction():
        context.run_migrations()


def run_migrations_online():
    """Run migrations in 'online' mode.

    In this scenario we need to create an Engine
    and associate a connection with the context.

    """

    # get the alembic section of the config file
    ini_section = config.get_section(config.config_ini_section)

    # if a database path was provided, override the one in alembic.ini
    database = context.get_x_argument(as_dictionary=True).get('database')
    if database:
        ini_section['sqlalchemy.url'] = "sqlite:///%s" % database
    else:
        ini_section = config.get_section(config.config_ini_section)

    connectable = engine_from_config(
        ini_section,
        prefix='sqlalchemy.',
        poolclass=pool.NullPool)

    with connectable.connect() as connection:
        context.configure(
            connection=connection,
            target_metadata=target_metadata
        )

        with context.begin_transaction():
            context.run_migrations()


if context.is_offline_mode():
    run_migrations_offline()
else:
    run_migrations_online()
